GlmS glucosamine-6-phosphate activated ribozyme

This RNA regulates the glmS gene by responding to concentrations of a specific metabolite, glucosamine-6-phosphate (GlcN6P), in addition to catalyzing a self-cleaving chemical reaction upon activation.

[4] The glmS gene encodes for an enzyme glutamine-fructose-6-phosphate amidotransferase, which catalyzes the formation of GlcN6P, a compound essential for cell wall biosynthesis, from fructose-6-phosphate and glutamine.

[3] Thus, when GlcN6P levels are high, the glmS ribozyme is activated and the mRNA transcript is degraded but in the absence of GlcN6P the gene continues to be translated into glutamine-fructose-6-phosphate amidotransferase and GlcN6P is produced.

[2] The ribozyme core contains a double pseudoknotted structure, which places the central helix P2.1 such that the scissile phosphate is nestled by the major groove.

[2] The roof of the active site is characterized by conserved base triples, which connect P2.1 and P2.2 stacks and the floor consists of a non-conserved G-U pair, which are splayed apart.

A 3D representation of the GlmS ribozyme. This is a view of the GlmS ribozyme bound to its catalytic cofactor. [ 1 ]
A 3D representation of the GlmS ribozyme. This view shows the pre-cleavage state of the Thermoanaerobacter tengcongensis glmS ribozyme bound to glucose-6-phosphate. [ 2 ]